Fig. 1. Site-selective antibody conjugates can be synthesised using (a) engineered thio-antibodies or on (b) native antibodies using disulfide re-bridging (amongst other methods); (c) thioaminoPD conjugates (in this case derived from site-selective cysteine modification of GFP S147C and para-anisidine) are stable to an excess of thiol environment.⁴⁵.